Source: https://mokxi.com/teachers/plans/power-electronics Updated: 2026-11-11 Lesson plan # Power electronics lesson plan Advanced: switches, inductors and heat: buck and boost converters from loose parts, PWM, MOSFET drivers, H bridges, efficiency, and a regulated supply you set from its formula. 4 chapters, 7 lessons, about 4 hours, no board. Every lesson runs in the browser, with nothing to install. Start a class from this course The unit ## Objectives and materials ### By the end, students can - Step voltage down and up with a switch, an inductor, a diode and a capacitor. - PWM, gate drive, and four switches around a motor. - Where the lost watts go, and linear against switching. - A regulated supply, set to the volt and signed off. ### Materials for the whole unit - Arduino Uno R3 - Battery: AA, coin cell, LiPo - Capacitor - D4184 dual MOSFET switch module - DC jack and adapter - DC motor - DC voltage source - Diode - DRV8871 motor driver - Filament lamp - Full-size breadboard - Function generator - Half breadboard - Inductor - IRF520 MOSFET module - LED - LM2596 buck converter module - LM317 regulator - MOSFET - Multimeter x 2 - Potentiometer - Resistor x 2 - Slide switch - Voltage regulator Every part is already on the simulator’s bench, so there is nothing to buy or hand out. The counts are the most any one lesson uses, if you build it on real breadboards too. Chapter 1. About 1 h ## Converters Step voltage down and up with a switch, an inductor, a diode and a capacitor. Lesson | Time | What students do The buck converter A buck converter from loose parts: a MOSFET switching 12 V twenty thousand times a second, an inductor, a diode and a capacitor, and why its output is the duty cycle times the input. | 30 min - Run it: 12 V in, about 6 V out - Why duty sets the voltage - Turn the duty down to 25 % - Up to 75 % - Where the current goes The boost converter The same four parts rearranged so the output climbs above the input: an inductor that kicks, a diode that catches the kick, and Vout = Vin / (1 - duty). | 30 min - Run it: 5 V in, nearly 10 V out - The kick - Duty 75 %: four times the input - Duty 25 %: just a little boost - Never run a boost with no load ### Materials - Capacitor - DC voltage source - Diode - Function generator - Inductor - MOSFET - Multimeter - Resistor ### Check for understanding Each student finishes "The boost converter" on their own, without opening the hints. The simulator checks 5 of its 5 steps as they go. Then ask each one to explain, in a sentence or two, the last thing it asked of them: "Never run a boost with no load". Chapter 2. About 1 h 40 min ## Switching PWM, gate drive, and four switches around a motor. Lesson | Time | What students do PWM and duty cycle A lamp dimmed by switching it fully on and fully off a thousand times a second: duty, frequency, the average a meter reads, and how analogWrite does the same thing. | 35 min - Run it and read the duty - The average is what counts - Dim it to 25 % - Bright: 90 % - Too slow: 5 Hz - Your own dimmer MOSFET drivers Two MOSFET boards on one pin: why the IRF520 module is only partly on from 5 V and off from 3.3 V, what a logic-level gate is, and what a gate driver is for. | 30 min - Run it and drive both boards - The IRF520 is only partly on - On a 3.3 V board - What a gate driver does - The driver checklist H bridges and current limits Four switches around a motor: forward, reverse, brake and coast on a DRV8871, why two switches on one side must never close together, and how the chip's current limit is set. | 35 min - Run it: forward - Speed is PWM on one input - Brake: both low sides on - Reverse - The current limit - Coast ### Materials - Arduino Uno R3 - Battery: AA, coin cell, LiPo - D4184 dual MOSFET switch module - DC motor - DC voltage source - DRV8871 motor driver - Filament lamp - Full-size breadboard - Function generator - IRF520 MOSFET module - MOSFET - Multimeter x 2 - Resistor x 2 - Slide switch ### Check for understanding Each student finishes "H bridges and current limits" on their own, without opening the hints. The simulator checks 6 of its 6 steps as they go. Then ask each one to explain, in a sentence or two, the last thing it asked of them: "Coast". Chapter 3. About 35 min ## Heat Where the lost watts go, and linear against switching. Lesson | Time | What students do Heat and efficiency The same 5 V made two ways from 12 V: a 7805 that burns the difference as heat and an LM2596 that switches, measured with two ammeters, and the heatsink math that decides which you need. | 35 min - Run it: the linear side - The switching side - Efficiency in two lines - Feed it 24 V - And the 7805 at 24 V - Linear or switching? ### Materials - DC voltage source - LM2596 buck converter module - Multimeter x 2 - Resistor x 2 - Voltage regulator ### Check for understanding Each student finishes "Heat and efficiency" on their own, without opening the hints. The simulator checks 6 of its 6 steps as they go. Then ask each one to explain, in a sentence or two, the last thing it asked of them: "Linear or switching?". Chapter 4. About 35 min ## Boss project A regulated supply, set to the volt and signed off. Lesson | Time | What students do Boss: a regulated supply Set an LM317 adjustable supply to exact voltages from its formula, find its dropout, prove it regulates when the input changes, and work out its heat. | 35 min - Run it: the supply at mid knob - Dial in exactly 5 V - Now 3.3 V - Find the dropout - Prove it regulates - Sign it off ### Materials - DC jack and adapter - Half breadboard - LED - LM317 regulator - Potentiometer - Resistor x 2 ### Check for understanding Each student finishes "Boss: a regulated supply" on their own, without opening the hints. The simulator checks 6 of its 6 steps as they go. Then ask each one to explain, in a sentence or two, the last thing it asked of them: "Sign it off". Your class ## Teach this unit as a class Start a class from this course and its 7 lessons are assigned in one go, in order. Students join with a six-character code or printed login cards, and each one’s work comes back to you. The class tools are free for 30 days for one class of up to 20 students, with no card. The lessons themselves are free either way. Start a class from this course See the demo class More units ## Other lesson plans Electronics basics 20 lessons, about 10 h. Embedded on the Arduino Uno 16 lessons, about 12 h. Embedded on the ESP32-C3 13 lessons, about 11 h. Embedded on the Raspberry Pi Pico 7 lessons, about 6 h. Build your own fight stick 5 lessons, about 4 h. Embedded on the STM32F411 6 lessons, about 6 h. C++ on a board 13 lessons, about 10 h. Digital logic and memory 4 lessons, about 4 h. Interactive devices on the Uno 9 lessons, about 8 h. From gates to a computer 23 lessons, about 16 h. Build a claw machine 8 lessons, about 6 h. 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